Save Uiimage Array in Nsuserdefaults

Save UIImage array in NSUserDefaults

You can easily save your image in documentDirectory as below:

let documentDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first
let fileURL = documentDirectory?.appendingPathComponent(yourImageName)


and then, you can give your image to UserDefaults

Save UIImage to UserDefault as Array , Swift

Something like this would work:

extension UserDefaults {
    func imageArray(forKey key: String) -> [UIImage]? {
        guard let array = self.array(forKey: key) as? [Data] else {
            return nil
        }
        return array.flatMap() { UIImage(data: $0) }
    }

    func set(_ imageArray: [UIImage], forKey key: String) {
        self.set(imageArray.flatMap({ UIImagePNGRepresentation($0) }), forKey: key)
    }
}

Usage:

let imageArray = [image1, image2, image3]
UserDefaults.standard.set(imageArray, forKey: "images")

let images = UserDefaults.standard.imageArray(forKey: "image")

However, I wouldn't recommend storing an array of images in UserDefaults. Storing the images as files would probably be more appropriate. You could then store their paths in UserDefaults.

saving and reading array of images with its data in NSUserDefaults or in Document Directory

You can't add images to user defaults, they aren't supported. You'll need to convert the image to data and save that instead (either to user defaults or, better, onto disk in a file...

imageArray.insert(UIImageJPEGRepresentation(img, 0.75), atIndex: self.imgIndex)

Error when trying to save image in NSUserDefaults using Swift

NSUserDefaults isn't just a big truck you can throw anything you want onto. It's a series of tubes which only specific types.

What you can save to NSUserDefaults:

• NSData
• NSString
• NSNumber
• NSDate
• NSArray
• NSDictionary

If you're trying to save anything else to NSUserDefaults, you typically need to archive it to an NSData object and store it (keeping in mind you'll have to unarchive it later when you need it back).

---

There are two ways to turn a UIImage object into data. There are functions for creating a PNG representation of the image or a JPEG representation of the image.

For the PNG:

let imageData = UIImagePNGRepresentation(yourImage)

For the JPEG:

let imageData = UIImageJPEGRepresentation(yourImage, 1.0)

where the second argument is a CGFloat representing the compression quality, with 0.0 being the lowest quality and 1.0 being the highest quality. Keep in mind that if you use JPEG, each time you compress and uncompress, if you're using anything but 1.0, you're going to degrade the quality over time. PNG is lossless so you won't degrade the image.

To get the image back out of the data object, there's an init method for UIImage to do this:

let yourImage = UIImage(data:imageData)

This method will work no matter how you converted the UIImage object to data.

In newer versions of Swift, the functions have been renamed, and reorganized, and are now invoked as:

For the PNG:

let imageData = yourImage.pngData()

For the JPEG:

let imageData = yourImage.jpegData(compressionQuality: 1.0)

Although Xcode will autocorrect the old versions for you

Saving NSMutableArray with UIImages to NSUserDefaults

Yes, you'll need to either use the UIImagePNGRepresentation or UIImageJPEGRepresentation functions to retrieve the image's binary data in the desired format, which you can then serialize into an NSArray.

An example:

UIImage *someImage = ...;
NSData *someImageData = UIImagePNGRepresentation(someImage);
[yourArray addObject:someImageData];

//...

[[NSUserDefaults standardUserDefaults] setObject:yourArray forKey:@"images"];

Persist Array of Images Swift

The error message is clear actually. UIImage is not a propertylist so you need to change it to a row data first. I'll put example below but FYI saving big data like images using NSUserDefaults is really not recommended. I'd use NSFileManager and put it in the user documents directory. anyway

var newPhotoKey = DefaultsKey<NSArray>("image")
cardImages = [(UIImage(named: "MyImageName.jpg")!)] 
var cardImagesRowdataArray: NSData = []
for image in cardImages {
    let imageData = UIImageJPEGRepresentation(image, 1.0)
    cardImagesRowdataArray.append(imageData)
}
Defaults[theKeyForStoringThisArray] = cardImagesRowdataArray 

var arrayToRetreiveWith = Defaults[theKeyForStoringThisArray] as! [NSData]
// here you can use UIImage(data: data) to get it back

If you don't insist on using SwiftyUserDefaults, you can save it in the user documents directory, here is how to do it

func saveImage(image: UIImage){
    if let imageData = UIImageJPEGRepresentation(image, 1.0) {
         let manager = NSFileManager()
         if let docUrl = manager.URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask).first{
             let uniqueName = NSDate.timeIntervalSinceReferenceDate()
             let url = docUrl.URLByAppendingPathComponent("\(uniqueName).jpg")
             imageData.writeToURL(url, atomically: true)
         }
     }
 }

---

Related Topics